Really weird problem. I'm working on my daughter's HP XW4100. The PS2 Mouse just goes dead. I have tried another PS2 mouse and now a Logitech wireless. I have read all sorts of posts online and not found my answer. I have run current AVG, Windows Defender, CCleaner, Glary Utilities, defrag, tried HP xw4100 mouse driver and Malewarebytes. Done a Chkdsk and run: "sfc /scannow"
I will reformat if I have to but am really curious what the problem is. My best guess is some sort of unfindable, (by me), registry problem. This machine has been through the mill - it had the "Publisher's Clearing House" toolbar on it when I got it. Anyone have a similar problem and fixed it? All sort of anecdotal fixes out there that don't work.

When you say "goes dead" do you mean it works for a while or it never works?
It could be a problem in the BIOS or the PS/2 port is fried, when booting up enter the BIOS and make sure the PS/2 port is enabled.

Follow up to old post: I gave the PC back to my daughter with a new wireless mouse and thought all was fine. Two months later, same problem. I gave her another computer. Took the problem machine: put in new HDD, new video card, two new burners (for fun) and went back to the old corded laser mouse. All is fine. Don't know what the problem actually was. A clean wipe did the trick. Go figure.